Manufacture of coeruleine sulphonic acids



Patented Jan. 17, 1928.

UNITED STATES PATENT OFFICE.

W'ILHELM HERZBERG, 0F BEELINWVELMERSDORF, AND GERHEARI) HOPIEE, OF BERLIN- TREPTOXV, (SEER-MANY, ASSIGHORS, IEEEIJE ASSIGNMENTS, TO GEASSELLI DYE- STUEF CORPORATION, OF IWE'W YUBK, N. 1., A CUEPORATION 01* DELAVJARE.

MANUFACTURE OF COERULEINE SULPHUNIC ACIDS.

No Drawing. Application fiwed April 2-8, 19536, Serial No. 103,358, and in Germany may 7, 1925.

10 no bisulphite compounds soluble in water.

The hydronyhydroquinone, oi? which the hydroxyhydroquinone-phthaleiue referred to 1s a derivative, has the formula:

By this invention the coeruleines can be converted into sulphonic acids which are easily soluble in water by treating them with fuming sulphuric acid in the presence of 5 boric acid. These sulphonic acids yield tast dyeings with the usual metal mordants. 4

The following example illustrates the invention, the parts being by weight:

4- parts of coeruleine having probably the formula:

crystallized boric acid in 30 parts of fuming sulphuric acid containing per cent of S0 and the whole is heated for 2 hours at 130 to 140 C. The mixture is poured on to ice and from the solution the coeruleine sulphonic acid is separated by salting out. It is a black powder which dissolves easily in water to a blue-black solution. it yields green tints on fibers moi-dented with a metal,

it is obvious to those skilled in the art that our present invention is not limited to the foregoing example or to the details given therein. It may be statedior instance that there may be substituted for the coeruleine the isoineride having probably the formula:

obtainable from hydroxhydroquinonephthaleine in which case there is obtained a sulphonic acid soluble in water to a dirty violet solution which yields with metal mordants blue to blue-black tints. In using such other coeruleine the proportions oi the ingredients as well as the other special conditions of reaction may be altered in order to obtain the best results. i

it cannot be stated with certainty What position the sulphonic acid group occupies in the coeruleine sulphonic acids which are obtainable by the herein-described treatment.

What we claim is,

1. Coeruleine sulphonio acids which are easily soluble in water yielding dark blueish to Violet solutions, which dye with metal moi-dents green to blue to blue-black tints, and which are obtainable by heating a coeruleine with turning sulphuric acid in the presence of boric acid.

2. The coeruleine sulphonic acid, which is easily soluble in water yielding a blue-black solution, which dyes with metal mordants green tints, and which is obtainable by heating the coeruleine obtained by heating pyrogallolphthaleiue with concentrated sulphuric acid, with fuming sulphuric acid in the preseuce of boric acid.

In testimony whereof we aihx our signatures.

lVlLHELM HERZBERG. GERHARD HOPPE. 

